Ultrasonic/Heat Staking Inserts

SI (Standard Inserts) Ultrasonic/Heat Staking Inserts are hexagonal-shaped body inserts that provide rotational torque resistance and knurling provides torque out resistance. The heat staking inserts are installed by pressing the insert into the mounting hole with a thermal press to melt the plastic surrounding the insert. The SI® brand inserts employ press-in and heat/ultrasonic installation methods to provide strong, reusable, and permanent threads in plastic. These SI® inserts are available in brass, stainless steel, and aluminum. The applications include wearables, smartphones, handheld devices, automotive, aerospace and defense, medical, transportation, industrial, and recreational equipment.

Results: 268
Select Image Part # Mfr. Description Datasheet Availability Pricing (USD) Filter the results in the table by unit price based on your quantity. Qty. RoHS ECAD Model Product Type Material Mounting Hole Size Length Outside Diameter Thread Size Packaging
SI Mounting Hardware ULTRASONIC INSERT, ALUMINUM 885In Stock
A tariff of 38% may be applied if shipping to the United States.
Min.: 1
Mult.: 1

Inserts Threaded Insert Aluminum 3.58 mm 5.56 mm 4.37 mm M2.5
SI Mounting Hardware ULTRASONIC INSERT, AL 594In Stock
10,000Expected 10/23/2026
Min.: 1
Mult.: 1

Inserts Threaded Insert Aluminum 3.89 mm 3.43 mm 4.37 mm M3
SI Mounting Hardware ULTRASONIC INSERT, STAINLESS 114In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Stainless Steel 0.349 in 0.3 in 0.375 in 1/4-20
SI Mounting Hardware ULTRASONIC INSERT, STAINLESS 1,265In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Stainless Steel 0.208 in 0.312 in 0.25 in 8-32
SI Mounting Hardware HI-TORQUE INSERT, ALUMINUM .300X.310 1/4-20 THREAD ULTRASONIC HEAT STAKING DIAGONAL 615In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Aluminum 0.316 in 0.3 in 0.342 in 1/4-20
SI Mounting Hardware HI-TORQUE INSERT, STAINLESS 2,700In Stock
5,250Expected 10/30/2026
Min.: 1
Mult.: 1

Inserts Threaded Insert Stainless Steel 4.81 mm 7.14 mm 5.33 mm M3.5
SI Mounting Hardware HI-TORQUE INSERT, BRASS 351In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Brass 4.81 mm 7.14 mm 6.35 mm M3.5 Bulk
SI Mounting Hardware ULTRASONIC INSERT, BRASS 9,088In Stock
28,000Expected 11/20/2026
A tariff of 45% may be applied if shipping to the United States.
Min.: 1
Mult.: 1

Inserts Threaded Insert Brass 3.89 mm 3.43 mm 4.37 mm M2.5
SI Mounting Hardware ULTRASONIC INSERT, BRASS 10,084In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Brass 4.7 mm 6.35 mm 5.56 mm M3
SI Mounting Hardware ULTRASONIC INSERT, STAINLESS 180In Stock
10,000Expected 9/7/2026
Min.: 1
Mult.: 1

Inserts Threaded Insert Stainless Steel 0.246 in 0.375 in 0.297 in 10-24
SI Mounting Hardware ULTRASONIC INSERT, STAINLESS 798In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Stainless Steel 0.107 in 0.188 in 0.141 in 2-56
SI Mounting Hardware HI-TORQUE INSERT, BRASS 353In Stock
A tariff of 10% may be applied if shipping to the United States.
Min.: 1
Mult.: 1

Inserts Threaded Insert Brass 0.316 in 0.5 in 0.342 in 1/4-20
SI Mounting Hardware HI-TORQUE INSERT, BRASS .300X.310 1/4-20 THREAD ULTRASONIC HEAT STAKING DIAGONAL 14In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Brass 0.316 in 0.3 in 0.342 in 1/4-20
SI Mounting Hardware HI-TORQUE INSERT, BRASS 5,355In Stock
10,000Expected 11/27/2026
Min.: 1
Mult.: 1

Inserts Threaded Insert Brass 5.67 mm 8.15 mm 6.17 mm M4
SI Mounting Hardware HI-TORQUE INSERT, BRASS 7.62X7.87 M6 THREAD ULTRASONIC HEAT STAKING DIAGONAL 198In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Brass 8.03 mm 7.62 mm M6
SI Mounting Hardware HI-TORQUE INSERT, BRASS 12.70X9.50 M8 THREAD ULTRASONIC HEAT STAKING DIAGONAL 3,016In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Brass 9.6 mm 12.7 mm 10.31 mm M8
SI Mounting Hardware ULTRASONIC INSERT, STAINLESS 954In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Stainless Steel 0.267 in 0.225 in 0.297 in 10-32
SI Mounting Hardware ULTRASONIC INSERT, STAINLESS 793In Stock
A tariff of 38% may be applied if shipping to the United States.
Min.: 1
Mult.: 1

Inserts Threaded Insert Stainless Steel 6.78 mm 5.72 mm 7.54 mm M5
SI Mounting Hardware HI-TORQUE INSERT 4,310In Stock
27,000On Order
A tariff of 38% may be applied if shipping to the United States.
Min.: 1
Mult.: 1

Inserts Threaded Insert Aluminum 4.01 mm 5.74 mm 4.55 mm M3
SI Mounting Hardware HI-TORQUE INSERT, ALUMINUM 3.43X3.86 M3 THREAD ULTRASONIC HEAT STAKING DIAGONAL 584In Stock
10,000Expected 10/30/2026
A tariff of 38% may be applied if shipping to the United States.
Min.: 1
Mult.: 1

Inserts Threaded Insert Aluminum 4.01 mm 3.43 mm M3
SI Mounting Hardware HI-TORQUE INSERT, BRASS 252In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Brass 0.127 in 0.157 in 0.147 in 2-56
SI Mounting Hardware HI-TORQUE INSERT, STAINLESS 151In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Stainless Steel 0.223 in 0.321 in 0.243 in 8-32
SI Mounting Hardware ISB-M4 DBL ENDED NUT 363In Stock
Min.: 1
Mult.: 1

Screws & Fasteners Nut, Double Ended Brass 5.62 mm 8.15 mm 6.22 mm M4
SI Mounting Hardware ULTRASONIC INSERT, ALUM 1,121In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Aluminum 6.25 mm 9.53 mm 7.54 mm M5
SI Mounting Hardware ULTRASONIC INSERT, BRASS 1,230In Stock
Min.: 1
Mult.: 1

Inserts Threaded Insert Brass 4.7 mm 6.35 mm 5.56 mm M3.5